Patent GB-480169-A (GB)
Title: The manufacture of azo dyestuffs and preparations for the production thereof
IPC: C09B41/00
Filed: 1936-08-14
Abstract: Azo dyes are made on the fibre from preparations containing coupling components and such diazoamino compounds as contain acid solubilizing groups in the radicle attached to the amino nitrogen and can be decomposed into the diazo compound and the amine by a reduction in the alkalinity of the preparation, by employing the diazoamino compounds at least partly in the form of salts with volatile bases, care being taken that non-volatile alkalies, are either absent, or if present are present in such a small amount, that after removal of the volatile bases part of the acid groups contained in the diazoamino compounds and in said coupling components remains free, and developing the dyestuff by eliminating said volatile bases from such preparations by heating in the presence of moisture, e.g. by steaming, whereby the acid groups set free by such elimination decompose said diazoamino compounds with the formation of the corresponding diazo compound and coupling of the diazo compound and the coupling component takes place.  The preparations may contain a volatile base in the free state which is also eliminated during development. Additional acid reacting vapour during steaming may be admitted. The development may take place simultaneously with that of vat dyes from their leuco compounds.  Examples (1)-(23) illustrate the manufacture of salts of diazoamino compounds with volatile bases: (1)-(2) diazotized 4-chlor-2-toluidine is coupled with 4-sulpho-2-aminobenzoic acid in aqueous pyridine quinoline, quinaldine or ammonium carbonate; the pyridine compound is salted out with ammonium chloride; (3) and (4) 5-sulpho-3-aminobenzoic acid and N-isobutyl-5-sulpho-2-aminobenzoic acid are used as in (2); (5) diazotized 4-chlor-2-toluidine is partially neutralized with ammonium carbonate and coupled with 2-aminoterephthalic acid or aniline-2 : 5-disulphonic acid in aqueous ammonium carbonate; (6) and (8) diazotized 2 : 5-dichloraniline is coupled with 4- or 5-sulpho-2-aminobenzoic acid in presence of ammonium carbonate; (7) diazotized 2 : 5-dichloraniline is coupled with 4-sulpho-2-aminobenzoic acid in presence of sodium carbonate and the product salted out with ammonium chloride; (9) and (10) diazotized 5-nitro-2-toluidine is neutralized with ammonium carbonate and coupled with the ammonium salt of 4- or 5-sulpho-2-aminobenzoic acid; (11) and (12) diazotized 4-chlor-2-toluidine is coupled with the di- or tri-ethylamine salt of 4-sulpho-2-aminobenzoic acid in presence of ammonium carbonate; (13) and (15) diazotized 2-amino-5-benzoylaminohydroquinonediethylether is coupled with sarcosine hydrochloride or 4-sulpho-2-aminobenzoic acid in presence of ammonium carbonate; (14) diazotized 4-chlor-2-anisidine is coupled as in (13) with 4-sulpho-2-aminobenzoic acid; (16) diazotized 4-chlor-2-toluidine is coupled as in (2) with 4-toluidine-2-sulphonic acid; (17), (18), (21)-(23) similar to (13) using methyltaurine, methylaminosuccinic acid, b -methylaminotetrahydronaphthalene monosulphonic acid, tetrahydroquinoline monosulphonic acid or pyrrolidine-a -carboxylic acid; (19) diazotized 2-amino-5-benzoylaminohydroquinone dimethylether is coupled with iminodiacetic acid as in (13); (20) diazotized 2-amino-5-benzoylamino-4 - methyl - 1 - anisole is coupled as in (13) with sarcosine hydrochloride.  Examples (24)-(35) illustrate the manufacture of printing solutions; (24) and (25) the o-toluidide of 2 : 3-oxynaphthoic acid is mixed with the ammonium salt of (2) and dissolved in diethylamine with or without a small amount of caustic soda; (26) the anilide of 2 : 3-oxynaphthoic acid and the ammonium salt of (13) are dissolved in benzyl alcohol, water and diethylamine and urea added, (27) the formaldehyde compound of 2 : 3-oxynaphthoic anilide and the ammonium salt of (13) are dissolved in thiodiglycol, water and isopropylamine and urea added; (28) the o-phenetidide of 2 : 3-oxynaphthoic acid and the ammonium salt of (2) are dissolved as in (27); (29) the o-toluidide of 2 : 3-oxynaphthoic acid and the ammonium salt of the diazoamino compound from diazotized 2-amino-5-benzoylaminohydroquinone diethylether and methylaminoethane sulphonic acid are dissolved as in (26); (30) diacetoacetyl-o-tolidine and the ammonium salt of (2) are dissolved in thiodiglycol, water and n-butylamine; (31) the o-phenetidide of 2 : 3-oxynaphthoic acid and the diethylamine salt of the diazoamino compound from diazotized 2 : 5-dichloraniline and 5-sulpho-2-aminobenzoic acid are dissolved in thiodiglycol, water and diethylamine; (32) and (33) 2 : 3-oxynaphthoic anilide and the ammonium salt of (19) or (18) are dissolved as in (26); (34) 2 : 3-oxynaphthoic anilide and the triethylamine salt of the diazoamino compound from diazotized 2 - amino - 5 - benzoylamino - 4-methyl-1-anisole and sarcosine are dissolved as in (31), (35) 2 : 3 - oxynaphthoic o - toluidide and the ammonium salt of (23) are dissolved as in (26).  In examples (36) the o-toluidide of 2 : 3-oxynaphthoic acid is mixed with the dry ammonium salt of (2) and (37) the o-phenetidide with the dry diethylamine salt of (31). Examples (38)-(46) illustrate the dyeing process using some of the above-mentioned compositions the colours being developed by steaming. According to (39) the dry preparations of (36) and (37) are mixed with caustic soda and diethylamine to form printing pastes.  In example (46) the following pastes are printed on the fibre and developed in the Mather Platt, (a) 2 : 3-oxynaphthoic o-toluidide, the ammonium salt of (2), diethylamine and starch tragacanth, (b) Bz2-Bz21-dimethoxydibenzanthrone, starch tragacanth, glycerine, potassium carbonate, Rongalite and water, a green and red print being obtained.  A table of components is also given.